Patterns of territorial space use by Shining Sunbeams ( Aglaeactis cupripennis ), tropical montane hummingbirds

Abstract

For many territorial hummingbirds, habitat use is influenced primarily by the interaction between resource acquisition and non-foraging behaviors such as territory advertisement and defense. Previous research has highlighted the importance of foraging-associated habitat features like resource density and distribution in determining the space-use patterns of hummingbirds. Less is known, however, about how habitat selection associated with non-foraging behaviors influences space use by territorial species. We used radio telemetry to examine patterns of territorial space use by Shining Sunbeams (Aglaeactis cupripennis) in high Andean montane forests near Manu National Park, Peru, and Bosque Comunal "El Carmen" near Chordeleg, Ecuador. We quantified within-territory habitat characteristics related to resource acquisition and non-foraging behaviors such as territory advertisement and defense. We found that Shining Sunbeams showed high use of core areas in territories where foraging effort was relatively low. We found no relationship, however, between the position of core areas and habitat characteristics associated with territory defense, predator avoidance, or other non-foraging behaviors. We also found no relationship between use of non-core areas and habitat use based on resource acquisition. Thus, patterns of territorial space use by Shining Sunbeams may be characterized by core areas not determined by foraging behavior. Further studies examining territorial behaviors and the influence of intrusion pressure will help identify the underlying determinants of territory space use by this and other species of Andean hummingbirds.

Tracking small animals in complex landscapes: a comparison of localisation workflows for automated radio telemetry systems

“…In general, telemetry data for hummingbirds is scant because they are very difficult to track (but see examples of hand-tracking in Hadley & Betts, 2009, Hazlehurst & Karubian, 2018, Zenzal Jr. et al, 2018, and thus very little is known about their movement ecology compared to other birds. Another study with high altitude Andean hummingbirds reports a similar territory size from handheld radio telemetry data (90th KDE average territory size for the Shining Sunbeam [Aglaeactis cupripennis] is 1.56 km 2 [Pavan et al, 2020], vs. 95th AKDE of 1.08 km 2 Great Sapphirewing and 0.86 km 2 Bronze-tailed Thornbill reported here). Hand-tracking individuals is limited to short time periods (some days) and small areas, is strongly biassed towards areas that are easier for researchers to traverse (Hazlehurst & Karubian, 2018), and may not produce sufficient data points to estimate home range sizes (Ward et al, 2013).…”

“…precluding the use of GPS trackers) and most attempts to track fast-moving animals, such as hummingbirds, have been limited to hand-tracking, limiting the studies to a few focal individuals (e.g. Pavan et al, 2020). We tested our ARTS grid by tagging two hummingbird species and collecting basic information on their movement trajectories and utilisation distributions.…”